ROS2 CLI cheatsheet

Listing stuff

ros2 pkg executables <pkgname>
ros2 node info <node>
ros2 topic list [-t]
ros2 service list [-t]
ros2 action list [-t]
ros2 param list

Where -t will add the types in square brackets.

Nodes

Run a <pkg>::<executable> node

ros2 run <pkg> <executable>

Set the <log-level> (DEBUG, INFO, WARN, ERROR or FATAL):

ros2 run <pkg> <executable> --ros-args --log-level <log-level>

Topics

Subscribe to and echo <topic-name>:

ros2 topic echo <topic-name>

Get the type and number of pub/subs to <topic-name>:

ros2 topic info <topic-name>

See how often <topic-name> is being published:

ros2 topic hz <topic-name>

Check a topic’s interface using the <type>:

ros2 interface show <type>

Publish to a topic:

ros2 topic pub <topic-name> <type> "<args>"

Where "<args>" are input in YAML syntax, ie: "{battery: {voltage: 12.7, capacity: 50.0}}"

Options:

• --once publishes the message once then exits
• --rate <freq> publishes the message at <freq> Hz

Services

Get the type of <service-name>:

ros2 service type <service-name>

Note: type std_srvs/srv/Empty sends and receives no data

Find services of a particular <type>:

ros2 service find <type>

Show a service’s interface using the <type>:

ros2 interface show <type>

Which prints:

<request structure>
---
<reponse structure>

Call a service using:

ros2 service call <service-name> <type> "<args>"

Like topics, "<args>" are input in YAML syntax, ie: "{gains: {kp: 1.0, ki: 0.0, kd: 0.1}}"

Actions

Information on <action> clients and servers:

ros2 action info /turtle1/rotate_absolute

Show an actions’s interface using the <type>:

ros2 interface show <type>

Which prints:

<request structure>
---
<result structure>
---
<feedback structure>

Send a goal to an <action>:

ros2 action send_goal <action> <type> "<args>"

"<args>" are input in YAML syntax, ie: "{setpoint: {x: 1.0, y: 0.0, z: 0.1}}"

Params

Get/set the value of a <node>:<param>

ros2 param get <node> <param>
ros2 param set <node> <param> <value>

Dumping and loading parameters:

ros2 param dump <node> # Saves params to <node>.yaml
ros2 run <pkg> <executable> \
    --ros-args --params-file <node>.yaml

Bag - data recording

Record <topics>:

ros2 bag record <topic-0> [<topic-1>] ... [<topic-N>]
ros2 bag record -o <name> <topic-0> [<topic-1>] ... [<topic-N>]

Use the -o flag to set a custome bag <name>. The default is rosbag2_yyyy_MM_dd-HH_mm_ss.

Get information about bag <name>:

ros2 bag info <name>

Play the information in bag <name>:

ros2 bag play <name>

Tools

rqt_console monitors log messages:

ros2 run rqt_console rqt_console

rqt_graph shows the current ROS graph:

rqt_graph

launch a bunch of nodes defined in a <launch-script>.py, see launch tutorial for more details

ros2 launch <launch-script>.py
ros2 launch <pkg> <launch-script>.py